YYCguy
Active Member
I really did try and read the last page’s comments thoroughly so I didn’t have to ask, but I just can’t find a previous reference to “CBTC”, so I have to foolishly admit that I don’t know what “CBTC” is. I’m sorry.
Green Line LRT | ?m | ?s | Calgary Transit
- Thread starter Surrealplaces
- Start date
darwink
Senior Member
Communication based train control is a standard for allowing the communication of train location at high precision, that can enable various train control systems, such as moving block in many contexts. A block is an area that one train can be in that a train control system will limit a second train from entering.
An intensive fixed block (like a block every 100 m or so) system can look very much like a moving block system, but at much higher infrastructure cost.
A modern moving block system to avoid the necessary infrastructure of fixed blocks requires that the signalling system can order trains to stop, and the train will then stop automatically, no matter where it is, instead of only at the start of the next fixed block.
The implementation is where the difficulty is. Edmonton tried to go too light on the infrastructure side, and ended up with trains that couldn't determine with precision where they were, as the system depended on counting wheel rotations, without a system to reliably reset location data (which can be as simple as cameras and QR codes, or RFID tags and readers).
